Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Patent
1994-01-10
1995-09-19
Springer, David B.
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
C07D25706
Patent
active
054516820
ABSTRACT:
A process of preparing 5-aminotetrazole ("5-AT") which proceeds at substantially neutral pH is disclosed. In the process, cyanamide or dicyandiamide and an azide salt are reacted at elevated temperature in the presence of an acid reagent. The acid reagent has a pK.sub.a in the range from about 3 to about 7. Large quantities of hydrazoic acid are not produced during the reaction. Upon completion of the reaction, the reaction mixture is acidified to a pH less than 3 to protonate the 5-AT. Several variations of the acidification step permit control of particle size and morphology. The precipitated particles are isolated to yield 5-AT.
REFERENCES:
patent: 3171249 (1965-02-01), Bell
patent: 3235558 (1966-02-01), Harrison et al.
patent: 3468730 (1969-09-01), Gawlick et al.
patent: 3557285 (1971-01-01), Enkoji et al.
patent: 3719604 (1973-03-01), Prior et al.
patent: 3739574 (1973-06-01), Godfrey
patent: 3778084 (1973-12-01), Sutherland et al.
patent: 3898112 (1975-08-01), Strecker et al.
patent: 4142029 (1979-02-01), Illy
patent: 4608102 (1986-08-01), Krampen et al.
patent: 4909549 (1990-03-01), Poole et al.
patent: 4948439 (1990-08-01), Poole et al.
patent: 5035757 (1991-07-01), Poole
patent: 5084118 (1992-01-01), Poole
patent: 5139588 (1992-08-01), Poole
patent: 5197758 (1993-03-01), Lund et al.
Frankel et al., "Derivatives of Dicyanamide," Jo. Org. Chem., vol. 28, pp. 2428-2431, Sep. 1963.
Lieber et al., "The Reaction of Nitrous Acid with Nitroaminoguanidine," J. Am. Chem. Soc., vol. 73, pp. 2327-2329, May 1951.
Lieber et al., "The Ultraviolet Absorption Spectra of 5-Nitroaminotetrazole and its Salts," J. Am. Chem. Soc., vol. 73, pp. 2329-2331, May 1951.
Lieber et al., "The Comparative Acidic Properties of Some 5-Substituted Tetrazoles," J. Am. Chem. Soc., vol. 73, pp. 1792-1795, Apr. 1951.
G. C. Chiang, "Preparation of 2-aminotriazine herbicide intermediates via metal dicyanimide ligand complexes," Chemical Abstracts, vol. 113, No. 231414f, p. 728, 1990.
Nakamura, et al., "Preparation of calcium dicyanamide aqueous solution as a pharmaceutical starting material," Chemical Abstracts, vol. 109, No. 148873b, p. 671, 1988.
Nakamura, et al., "A process for the preparation of dicyanamide metal salts as intermediates for antimicrobials," Chemical Abstracts, vol. 109, No. 210568m, p. 618, 1988.
W. P. Norris and R. A. Henry, "Cyanoguanyl Azide Chemistry," pp. 650-660, Mar. 1964.
M. Kuhn and R. Mecke, "IR-Spektroskopische Untersuchungen am Dicyanamid-Anion," Chem. Ber., vol. 94, pp. 3010-3015, 1961.
Joseph S. Mihina, et al., "The Reaction of Nitriles With Hydrazoic Acid: Synthesis of Monosubstituted Tetrazoles," Kedzie Chemical Lab., pp. 1082-1092, Apr. 1950.
R. Stolle, "5-Aminotetrazole," Chemical Abstracts, 10-Organic Chemistry, vol. 23, p. 4471, 1929.
R. Stolle et al., "Zur Kenntnis des Amino-5-tetrazols," Chem. Ber., vol. 62, pp. 1118-1127, 1929.
William L. Burdick, "Some Ammono-Carbonic Acids and Their Reactions in Liquid Ammonia," The Journal of the American Chemical Society, vol. 47, No. 6, pp. 1485-1491, Jun. 1925.
The Merck Index 9th Ed Merck & Co Rahway, N.J. (1976).
Highsmith Thomas K.
Lund Gary K.
Lyons Ronald L.
Springer David B.
Thiokol Corporation
LandOfFree
Method for synthesizing 5-aminotetrazole does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for synthesizing 5-aminotetrazole, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for synthesizing 5-aminotetrazole will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1829275